Production of standard or consumer envelopes in the prior art results in an envelope with folds (flaps) on four sides. The envelope paper stock is die cut to the desired shape, pre-glued on three sides and folded in four directions. These types of consumer envelopes are packaged and sold in boxes for later hand placing of the contents and manual gluing by the owner.
Mass mailings or direct mail requires that the envelope be produced in-line with the contents and be machine stuffed and sealed in an automated fashion to reach economies of scale and efficiency to produce very large numbers in the mass mailing market. The mass mailing market has reached sizes requiring 20 to 50 million pieces of completely addressed pieces stuffed, folded and glued ready for drop mailing by a single date. These requirements have driven the industry to produce in-line envelope stuffing and mailing machines which can handle these large numbers.
Prior art industry machines have produced the contents of the envelope and the envelope in a single pass through a machine for stuffing and mailing to reach economies of scale. The problem with the prior art automated machines is that the envelopes cut, glued and stuffed for mailing have only been folded in two directions. This results in an envelope that has only two flaps, top and bottom, and which has the sides flat-cut and glued together to complete the seal. In contrast to this, manual mailing envelopes and personal mail envelopes are folded in four directions resulting in four flaps with the side flaps glued to the bottom flap and with the top flap pre-glued and left open for later manual stuffing and sealing. The recipient of the mass mailing will readily recognize that a manually stuffed envelope is quite different from an automated stuffed envelope by the folding and gluing differences of the envelope. Since this recognition occurs before opening the envelope, a lower response rate to the mass mailing will result due to immediate discarding.
There is, therefore, a need in the prior art for an automated way of producing mass mailings in which the envelopes are folded in four directions to produce four flaps, the side flaps being glued to the bottom flap, stuffed in an in-line process and the top flap glued to the bottom flap for final sealing of the contents. There is a need in the prior art to produce a high volume of glued, folded, stuffed and sealed mass mailings with no reduction of current machine speeds to meet the present day mass mailing requirements with a product that is indistinguishable from a personally stuffed and mailed envelope.
There is also a need in the prior art for a method of making an envelope by high speed printing and stuffing machines that will produce an envelope from a continuous paper web with one of the flaps of the envelope, corresponding to one of the directions of folding in the process, to be folded in the opposite direction of the web.